Unsymmetry of Tension and Compression in Titanium Single-crystal Nanopillars Based on Molecular Dynamics Simulation

P Li and Q Chu and SL Yan and XH Ji and KM Xue, RARE METAL MATERIALS AND ENGINEERING, 48, 1835-1840 (2019).

The plastic deformation mechanisms of the titanium single-crystal nanopillars under both tension and compression were studied with the molecular dynamics simulation method. In this work, the research focuses on two aspects around the microscopic deformation mechanisms: stress- strain analysis and the evolution of atomistic configuration. The results indicate that the 10 (1) over bar2) twinning and stacking fault dominate the tension deformation along the 0001 direction. The < a > slip is the principal factor leading to the initial yielding and then the < c+a > pyramidal slip occurs to coordinate both vertical and horizontal strains for the compression condition along the 0001 direction. Additionally, no twinning is found in compression. Besides the conventional 10 (1) over bar2 plane, semi-coherent basal-prismatic interfaces between parent and reoriented crystal are also observed under tensile loading.